Apparatus for launching a soil burrowing mole

ABSTRACT

Apparatus and method are disclosed for launching a linear impact subsoil penetrator (mole). The apparatus includes a support platform which can be positioned to provide a selected angle of attack for the mole relative to the soil surface. The linear impact drive of the mole is started; and a restraining force is applied by the apparatus to the sides of the mole to create artificial tunnel traction and prevent the backward slip of the mole. This insures that operation of the mole&#39;&#39;s linear propulsion system will produce only forward motion and move the mole&#39;&#39;s nose into the soil.

[ June 4, 1974 1 APPARATUS FOR LAUNCHING A SO lL 3,151,687 10/1964 Sato et 3,354,969 11/1967 BURROWING MOLE [75] Inventor: lgguglas Rodney Steen, Mt. Bethe], y Examiner Emest R. Purser Attorney, Agent, or Firm-C. E. Graves [73] V Assignee: Bell Telephone Laboratories,

[57] ABSTRACT Apparatus and method are disclosed for launchin linear impact subsoil penetrator (mole). The a Incorporated, Murray Hill, N].

pparacludes -a support platform which can be posid to provide a selected angle of attack for the mole relative to the soil surface. The linear impact rive of the mole is started; and a restraining force is applied by the apparatus to the sides of the mole to create artificial tunnel traction and prevent the backward slip of the mole. This insures that operation of the moles linear propulsion system will produce only forward motion and move the moles nose into the .m n L so .1 mfi d m o? 28 H 78 7 H2 1 1 7 ,m2 3 05 m S M m ,H T 9 m4; N Wwa E My r w mm 9 P M 3 1 m m m cT 7 H m MB m 2 6 n n 1 IT. L L mH m Io m m 0 m, mCA RD 3 M E ..v 3 l T n .e O "SM 1 N L7 f5 N .11 U C d M. 0 no. m F A U .mF N .H H m 2 2 5 55 5 [fl R24 965 4/1961 Kirkpatrick.;..................... 175/94 X 1.028.523 6/1912 Anderson 61/72.? X 2 Claims, 6 Drawing Figures PATENTEDJUM 41974 8 4 SHEET 1 0f 6 FIG.

PATENTEDJUM 4mm (1814192 swears FIG. 2

PATENTEnJun 4:914.

SHEUISUFG PATENTEDJUH 4 I374 SHEET 5 OF 6 FIG. 6

APPARATUS FOR LAUNCHING A SOIL BURROWING MOLE FIELD OF THE INVENTION This invention relates to subsoil penetrators for moles and, more specifically, to apparatus and method for launching the mole into the soil.

BACKGROUND OF THE INVENTION The mole is a guided subsoil missile designed to form tunnels for the placement of utility services such as telephone distribution cable or service wire.

The moles may be steered in the manner disclosed by J. C. Coyne in US. Pat. No. 3,630,295 issued Dec. 28, 1971. The steering scheme disclosed therein involves an earth-burrowing device with an articulatable tail with an active fin or fins. The fin stabilizes the device in steering situations where control would otherwise be lost, by permitting simultaneous steering and roll actrons.

The guidance of such moles from above the ground was disclosed by I. C. Coyne in U.S. Pat. No. 3,589,454 issued June 29, 1971. As disclosed therein the subterranean missile is guided along any desired underground trajectory defined with reference to a coordinate system including the plane of a dipole-quadrupole antenna system laid on the ground above.

A typical propulsion system for the mole was described by J. C. Coyne and A. R. Smith in US. Pat. No. 3,642,076 issued Feb. l5, 1972. The propulsion cycle described therein is characterized by the impact of an oscillating hammer upon an interior anvil, and by the return of the hammer to its starting position by the force of a reaction piston acting on the hammer. While the reaction piston does work on the hammer, the opposite force thus produced on the mole nose causes a further soil penetration.

It can be seen that the mole has become a sophisticated system in terms of guidance and propulsion. However, it has until now been necessary to manually bury the mole in order to launch it. Only in this way was it possible to surround the mole with soil to provide necessary tunnel traction and permit the propulsion system to move it forward.

It is therefore an object of my invention to permit the guided launching of a mole from above the surface of the soil by using its own propulsion system.

It is a further object of my invention to permit the mole to be launched at any desired angle of attack relative to the surface of the soil.

SUMMARY OF THE INVENTION Underground burrowing devices penetrate the soil due to a linear impulse propulsion system. Backward tunnel movement due to the forward thrust of this impulse is resisted by tunnel traction or the restraint exerted on the device by the surrounding soil. To permit the device to be launched from above the soil surface, using its own propulsion system, an artificial tunnel environment is created pursuant to the invention.

In a specific embodiment of the invention, a channel positions the mole to be launched at a desired angle of attack relative to the soil surface. A cam-actuated snubbing device forces the mole against the sides of the channel. This force creates sufficient pseudo-tunnel traction to permit the propulsion system to advance the mole. Advantageously, the snubbing device is selectively positionable above the mole by virtue of a guide track into which the cam fits. The snubbing action is achieved by a separate large lever arm-snubber system in which the cam is the fulcrum.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of launching apparatus embodying my invention;

FIG. 2 is an elevation view of the apparatus of FIG. 1 shown in position for towing to a launch site;

FIG. 3 is an elevation view of the apparatus of FIG. 1 shown ready to launch a burrowing device;

FIG. 4 is an elevation view of the apparatus of FIG. 1 showing the device partially launched;

FIG. 5 is an elevation view of the apparatus of FIG. 1 showing the device almost completely launched; and

FIG. 6 is a perspective view of the apparatus of FIG. 1 with the device completely launched.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT FIG. 1 shows a mole 11 in position to be launched into the soil surface 50 by launch apparatus 12. Launch apparatus 12 is a portable and adjustable supporting platform carried on two wheels 13. A V-shaped trough 14 runs substantially the length of apparatus 12 and supports the mole 11. At the launch end of trough 14 are a pair of flared anchor pads 15 each having several holes 16. Above, and along the launch end half of trough 14, are parallel tracks 17. Pivot bar 18 rides in tracks 17 and rotates to wedge restraining block 19 against mole 11 by cam action when a force is applied to lever 21.

The angle of attack the launch end of mole 11 makes with the soil surface 50 is dependent upon the positioning of the elevator mechanism at the other end of launch apparatus 12. The elevator mechanism comprises a base support 23, slotted elevator arms 24. locking wing nuts 25 and elevator handles 26.

With the elevator mechanism in the position shown in FIG. 2, launch apparatus 12 may be towed to the launch site. In the towing position, mole 11 may be lashed to trough l4 (lashings not shown) to provide transport for the mole. In this position, all the weight of apparatus 12 and mole 11 is carried by wheels 13 and no other part of the apparatus is in contact with the ground. Built into support 23 is a tow bar 28 which helps support apparatus 12 when in the launch position and serves as an attaching point to a towing vehicle (not shown) for transportation to the launch site.

Upon reaching the launch site, apparatus 12 is moved into the launch position shown in FIG. 3. By lifting on handles 26, apparatus 12 rotates around the wheels 13 until anchor pads 15 are in contact with soil surface 50. This could be done easily be one man due to the balanced weight distribution of apparatus 12 and mole 11 on the wheels 13. By loosening nuts 25, base support 23 can be lowered to contact the surface 50. Tightening nuts 25 locks elevator arm 24 in this position and handles 26 may be released- Although the elevating mechanism is adjustable to compensate for rough terrain, the optimum angle of attack of the mole to the soil surface is approximately 26 and pads 15 are positioned accordingly. As soon as the restraining mechanism comprising pivot 18, block 19 and lines 21 are positioned in tracks 17, the launch apparatus 12 is ready to advance mole 11 under soil surface 50.

One additional procedure is recommended, although it may not be necessary with some soil conditions. Since the launching of mole 11 generates substantial thrust and vibration, it is recommended that hold-down pins (not shown) be driven into the ground through holes 16 in pads 15. This will prevent undesirable movement of apparatus 12 during the launch.

By rotating arm 21 around pivot 18, block 19 exerts a restraining force on the side of mole 11. The purpose of the restraining force is to create an artificial tunnel environment for mole 11. This generates sufficient tunnel traction to permit the propulsion system to advance mole 11 along trough 14 while block 19 snubs the mole and prevents any backward slippage.

As can be seen in FIG. 4, as the nose of mole 11 ad vances under the surface 50, the position of pivot 18 is moved along tracks 17 to maintain block 19 in its most effective position along mole 11. When mole 11 has advanced into the ground to the point shown in FIG. 5, block 19 is no longer required since real tunnel traction is provided to the mole by the soil. At this position, the launch mechanism comprising lever 21, block 19 and pivot 18 may be removed from tracks 17. Trough 14 will continue to support the end of mole 11 until it is completely under surface 50. Once the body of mole 11 is completely under surface 50, trough l4 continues to serve the function, shown in F IG. 6, of guiding control and propulsion cables 30 to prevent coiling and fouling of the cables.

it is to be understood that the embodiment described above is illustrative only. Various modifications may be made thereto by persons skilled in the art without departing from the spirit and scope of my invention.

What is claimed is: 1. Launch apparatus for inserting a linear impact burrowing device into the soil, the apparatus comprising means for positioning the device to have a generally downward angle of attack to the soil surface comprising a trough for supporting the device, and means for rotating the trough relative to the soil surface and for locking the trough in a selected position to permit the device to be given a desired angle of attack relative to the soil surface; and means including said trough and cam-actuated snubbing means located above the trough and pivoted to rotate and transmit a force to the supported device, for applying a restraining force to the device to prevent backward slippage so that the thrust of the propulsion impulse produces only forward movement of the device. 2. Apparatus in accordance with claim 1 wherein the cam-actuated snubbing means includes a track in which the pivot is located, the track extending substantially parallel to and along the length of the trough to permit the snubbing means to be positioned progressively along the track as the mole is advanced. 

1. Launch apparatus for inserting a linear impact burrowing device into the soil, the apparatus comprising means for positioning the device to have a generally downward angle of attack to the soil surface comprising a trough for supporting the device, and means for rotating the trough relative to the soil surface and for locking the trough in a selected position to permit the device to be given a desired angle of attack relative to the soil surface; and means including said trough and cam-actuated snubbing means located above the trough and pivoted to rotate and transmit a force to the supported device, for applying a restraining force to the device to prevent backward slippage so that the thrust of the propulsion impulse produces only forward movement of the device.
 2. Apparatus in accordance with claim 1 wherein the cam-actuated snubbing means includes a track in which the pivot is located, the track extending substantially parallel to and along the length of the trough to permit the snubbing means to be positioned progressively along the track as the mole is advanced. 